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CryptoHack

A free, fun platform for learning modern cryptography

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Learn By Doing

Learn about modern cryptography by solving a series of interactive puzzles and challenges. Get to know the ciphers and protocols that secure the digital world by breaking them.

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Level Up

Earn points by solving challenges. Finish categories to earn trophies and gain levels to track your progress. Can you reach the top of the scoreboard?

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Fresh Challenges

We are constantly creating new challenges to keep your crypto knowledge up to date. Expect exciting brainteasers and whole new categories as the site continues to grow.

New Challenges
Do you have good eyes? (Breizh CTF) CTF Archive 0
RSATogether (ECSC 2024 (Italy)) CTF Archive 0
Authentification 1 (Breizh CTF) CTF Archive 0
One Round Crypto (ECSC 2024 (Italy)) CTF Archive 0
Greatest Common Multiple (CODEGATE CTF) CTF Archive 0
Weekly Top Users
#1 yats 2500
#2 LvKNnT 2200
#3 kiseia 1990
#4 xinyi_y 1950
#5 page0egap 1925
Recent Solves
Bytes and Big Integers Joan05
Too Many Errors DQH
ASCII gaia2025
Modular Arithmetic 2 aceiii
Base64 isareich
Recent Solutions
ProSign 3 TanR 0
Curveball TanR 0
CSIDH Key Exchange Nhan_LAPTOP 0
Adrien's Signs nono40 1
Let's Decrypt nullablevoidptr 0

Level Up

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